Sound-modifying means for phonographs



J..HAJEK. souwo MODIFYING MEANS FOR PHONQGRAPHS. APPLICATION FILED JAN. 14, 1920.

1,356,983. Patented Oct. 26,1920.

III 1 1 III/IlIIII/I m FIGLZ.

IN VENT'OE.

JOSEPH HAJ'EK, OF CARNEGIE, PENNSYLVANIA.

SOUND-MODIFYING. MEANS FOR PHONOGRAPHS.

Application filed January 14, 1920.

To all whom it may concern.

Be it known that I, JOSEPH HAJEK, a citizen of the Republic of Czechoslovakia, residing at Carnegie, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Sound-Modifying Means for Phonographs, of which the following is a specification.

This invention relates to sound modifying means particularly adaptable to phonographs and has for its object the provision of a movable flexible member of relatively varying density for interrupting the sound vibrations as they are emitted from the phonograph sound conveyer or chamber.

With these and other objects in view my invention consists in the novel construction, combination and relative position of the parts and members hereinafter described and shown in the accompanying drawings, and particularly pointed out in the appended claim.

Referring to the drawing in which like reference characters indicate like or corres muding parts:

Figure l is a front elevation of a phonograph embodying my invention. Fig. 2 is a cross-section taken on line 2-2 of Fig. 1. Fig. 3 shows an enlarged detail of spring clip and bearing.

Referring to the drawings which show one form of my invention. 10 indicates a phonograph cabinet having a motor chamber 11, a motor 12. turntable 13, reproducer l4. tone-arm l5, and a sound convcyer or chamber 16.

fixed or stationary open or slotted grating 17 protects the end of the sound conveyer 1t and permits the escape of sound vibrations therethrough.

Specification of Letters Patent.

Patented Oct. 26, 1920. Serial No. 351,303.

Between the stationary grating 17 and the end 16 of the sound conveyer 16, I place a movable or reciprocating flexible member 18, which may be of cloth or woven fiber or metal. This flexible member 18 is woven in such manner that portions of same Will vary in density. This relative density may be arranged progressively, uniformly or in any other relation. The member 18 being flexible, spools or cylinders 19 and 20 are provided, for winding same from one to the other and each one operable by a crank 21.

The cylinders 19 and 20 are mounted on shafts or spindles 22, the ends of which are engaged in spring clasp friction bearings 23.

If the flexible member varies in density as here provided, it is obvious that by operating the cranks 21 to reciprocate the member 18 from one spool to the other, the sound vibrations coming from the chamber 16 will be interrupted by wall 18 and the emitted sounds will be accordingly varied.

It is thought that the foregoing description and illustrations clearly disclose the construction and operation of the. invention, hence a more extended explanation is omitted.

I claim:

In a sound reproducing machine, the combination of a sound conveyer. and means for varying the intensity of the emitted sounds from said conveyer comprising a pair of rollers and a flexible member of varying density arranged for movement from one roller to the other and vice versa.

In witness whereof I have hereunto subscribed my name thisseventh day of January 1920.

JOSEPH HAJEK. 

